‘They Watch Us From the Sky.’

PHILADELPHIA — Most baseball players stopped wearing high-cut stirrups years ago, well before Pablo López was born to Danny López and Agnedis Serra in Venezuela in 1996. López, one of two young aces for the Miami Marlins, likes the throwback style but wears stirrups to remind him of Danny, who died of a heart attack two summers ago.

“Smartest guy I’ve ever known,” Pablo López said here on Monday while sitting on the Marlins bench before a game with the Phillies. “You know how they say there’s book-smart people and street-smart people? He was the smartest person I’ve met overall, in every way.”

López was something of a miracle baby; Danny, an internist, was a prostate cancer survivor who did not believe he could have children. He had been an amateur, stirrups-wearing outfielder in Venezuela and delighted in his son’s talent for the game. He took Pablo to his pro tryouts after Agnedis, a pathologist, was killed in a car accident when Pablo was 11.

Sandy Alcantara, the Marlins’ No. 1 starter and perhaps the early leader for the National League Cy Young Award, has felt similar grief. He speaks every day with his father, Confesor, who lives in the Dominican Republic. But Alcantara lost his mother, Francisca Montera, to lung cancer last July, nearly four years after a brother, Lexi, died in a motorcycle accident.

The pitchers bring more to the mound than the responsibility of leading a young staff. They are motivated by loss and bound by a higher sense of purpose.

“We lose, like I say, the captain of our families,” Alcantara said. “Our families are really important for us. We’ve got to keep positive and we know they watch us from the sky.”

Alcantara, like López, is a 26-year-old right-hander who represents the future of a franchise that has missed the playoffs each full season since winning the 2003 World Series. Through Wednesday they ranked first and second among N.L. pitchers in wins above replacement, according to Baseball Reference, with Alcantara — the leader, with 4 — blending durability and dominance in a way no other pitcher does.

Through Wednesday, Alcantara had worked 297 innings since the start of the 2021 season, easily the most in the majors (Adam Wainwright of the St. Louis Cardinals was second, with 279 ⅓). He has reached at least seven innings in each of his last seven starts, the majors’ longest streak since the Mets’ Jacob deGrom closed out his 2019 Cy Young season with eight in a row.

“His ability to get stronger as the game goes on is really remarkable,” catcher Jacob Stallings said. “He starts getting in another gear when he can sense the sixth, seventh and eighth being his innings — and the ninth, too. He’s been phenomenal.”

While most pitchers lose effectiveness as a game goes on, Alcantara, who is 6-2 with a 1.68 earned run average, indeed gets better. Opponents are hitting .215 off him in their first two plate appearances of a game, but just .156 thereafter. Alcantara uses five pitches — four- and two-seam fastballs, changeup, slider and curveball — and varies his speeds on everything.

The wide repertoire helps Alcantara last longer in games than most power pitchers, which is a point of pride. He can name the only others besides him to work 200 innings last season — Walker Buehler, Zack Wheeler and Wainwright — and thinks beyond the next pitch. Hunting for strikeouts from the start can quickly elevate a pitch count.

“I start the game with my best stuff, but I don’t try to do too much,” said Alcantara, who came to the Marlins from St. Louis in a 2017 trade for Marcell Ozuna. “But after the fifth or sixth inning, I’ve got to take out of my pocket all that I have and use it. Sometimes I start a game from the first to fifth inning at 96, 97, sometimes 98. But after the fifth, I’ve just got to use my power — 99 to 100, maybe to 101.”

The changeup, in particular, stands out for both Alcantara and López, who is 4-2 with a 2.30 E.R.A. According to Fangraphs, Alcantara throws his changeup harder than any other qualified pitcher, an average of 91.8 miles per hour. López, meanwhile, throws his changeup more often than any other pitcher, using it 37.7 percent of the time.

Mel Stottlemyre Jr., the Marlins’ pitching coach, said both pitches act somewhat like a splitter, closer in velocity to their fastball than a typical changeup, but with more movement.

“They both throw with great arm speed, and there’s no sense of ‘I’m going to try to place this pitch,’” Stottlemyre said. “They’ve kept power at the forefront, so they maximize their movement and their finish to the pitch. They’re special.”

The pitches, yes, but also the people. When Stottlemyre’s father Mel Sr., the longtime pitcher and coach, died of multiple myeloma in January 2019, Alcantara and López both called to console him. Stottlemyre, who had just recently joined the Marlins, has since helped both pitchers through their personal trials.

“Sharing what that feels like, being able to have that inspire and give purpose and meaning to everything you do — we’ve all three spent a lot of time talking about that,” said Stottlemyre, who is 58. “It hurt me, too, watching them, because I only know how I handled my dad’s death. And to be young? I got to live with my dad for almost all of my life, and to experience all the great times. That got taken away from them.”

Stottlemyre recognizes his father’s influence in the way he speaks with his pitchers. He invests time in building relationships, earning their affection — the pitchers wear T-shirts calling themselves “Stott’s Tots” — and trust. He has opened up about his younger brother, Jason, who died of leukemia in 1981, and said he has never been as close to two pitchers as he is to Alcantara and López.

“I see him not only as a pitching coach,” López said, “but also as a father figure and a great role model.”

López’s father encouraged him to pursue a pro career with the Seattle Mariners at 16 years old, when he had another heady option: medical school at La Universidad del Zulia, his parents’ alma mater. López had graduated from high school at age 15 — mastering four languages along the way — and his mother’s side of the family cautioned that the baseball world could be very uncertain. Danny reasoned that medical school could always be a backup plan for baseball, but not the other way around. That logic won out, though López has struggled at times with the burdens of high achievement.

“My family comes from a very smart background, so I put a lot of pressure on myself and I’ve had to tone it down,” said López, who was traded from Seattle to Miami for reliever David Phelps in 2017.

“Just try to be the best version of yourself. You don’t have to be better than anyone, you just have to be better than you were on your last test, you know? And I think I translate that to baseball, like: I just have to be better than I was five days ago.”

López was never better than he was last July 11 against Atlanta, when he became the first pitcher ever to open a game with nine consecutive strikeouts. It was López’s last start before a rotator-cuff injury that would cost him more than two months, but the record still carries deep meaning.

“It was the one-year anniversary of my dad passing away,” Lopez said. “To do what I did, I needed some help — and I think he provided it somehow, some way.”

The Marlins do not look to López the way they do to Alcantara, whose five-year, $56 million contract, signed last November, is the richest on the team’s thrifty payroll. Stottlemyre said Alcantara would probably throw 220 innings this season (roughly double López’s career high), and if he wins the Cy Young, he would be the first pitcher in club history to do so.

Alcantara said he has heard the early awards talk but has not dwelled on it. He is more reserved than López, a man of fewer words in English or Spanish, but likewise honors his family with his equipment. On the outside of Alcantara’s red Rawlings glove, in blue capital letters, is a stitched tribute: RIP MOM & LEXI.

“I know my mom is so happy,” Alcantara said, “because I’m here and she’s supporting me from there.”